Flap-plate flame arrestor

Abstract

A flame arrester uses two flap plates mounted at the center of its housing to prevent the propagation of a flame front caused by the deflagration of a flammable fluid. During the normal flow of fluid, the flap plates are open with a small gap between them facing the direction of flow. When a deflagration occurs, the pressure wave that precedes the flame front is caught by the gap between the two flap plates and pushing them to a closed poison against a circular stop ring in the wall of the housing, thereby preventing the propagation of the flame front.

1 . A flame arrester for preventing propagation of a flame front produced by a flammable material flowing in a conduit, comprising: 
 a chamber with tapered ends adapted for connection to the conduit;    a shaft mounted in the chamber across a plane perpendicular to a direction of flow of said flammable material;    first and second flap plates pivotally mounted on the shaft, said flap plates being freely rotatable between an open position toward said direction of flow and a closed position substantially perpendicular to said direction of flow;    a means for limiting a motion of each of said first and second flap plates to said closed position when the flap plates rotate between the open and closed positions; and    a means for maintaining an opening between the flap plates in the open position;    whereby a pressure wave traveling in a direction opposite to said direction of flow causes the first and second flaps plates to rotate to said closed position and rest against said limiting means.    
   
   
       2 . The flame arrester of  claim 1 , wherein said limiting means comprises a stop ring attached to an interior wall of the chamber.  
   
   
       3 . The flame arrester of  claim 1 , wherein the chamber is cylindrical.  
   
   
       4 . The flame arrester of  claim 2 , wherein the chamber is cylindrical.  
   
   
       5 . The flame arrester of  claim 1 , wherein the chamber is rectangular and the shaft is disposed symmetrically across a section of the chamber.  
   
   
       6 . The flame arrester of  claim 1 , wherein said opening between the flap plates in the opening position is at least 30 degrees.  
   
   
       7 . The flame arrester of  claim 2 , wherein said opening between the flap plates in the open position is at least 30 degrees.  
   
   
       8 . The flame arrester of  claim 4 , wherein said opening between the flap plates in the open position is at least 30 degrees.  
   
   
       9 . The flame arrester of  claim 5 , wherein said opening between the flap plates in the open position is at least 30 degrees.  
   
   
       10 . The flame arrester of  claim 1 , further including latching means disposed upon said chamber such that said first and second flap plates are engaged in the closed position.